Re: [PATCH v8 perf,bpf 10/15] perf-top: add option --no-bpf-event

From: Arnaldo Carvalho de Melo
Date: Mon Mar 11 2019 - 17:17:16 EST


Em Mon, Mar 11, 2019 at 09:07:20PM +0000, Song Liu escreveu:
>
>
> > On Mar 11, 2019, at 12:55 PM, Song Liu <songliubraving@xxxxxx> wrote:
> >
> > bpf events should be tracked by default for perf-top. This patch makes it
> > on by default, and adds option to disable bpf events.
> >
> > Signed-off-by: Song Liu <songliubraving@xxxxxx>
> > ---
> > tools/perf/builtin-top.c | 3 +++
> > tools/perf/util/top.h | 1 +
> > 2 files changed, 4 insertions(+)
> >
> > diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
> > index 27d8d42e0a4d..ccdf5689452f 100644
> > --- a/tools/perf/builtin-top.c
> > +++ b/tools/perf/builtin-top.c
> > @@ -1492,6 +1492,7 @@ int cmd_top(int argc, const char **argv)
> > "Display raw encoding of assembly instructions (default)"),
> > OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel,
> > "Enable kernel symbol demangling"),
> > + OPT_BOOLEAN(0, "no-bpf-event", &top.no_bpf_event, "do not record bpf events"),
> > OPT_STRING(0, "objdump", &top.annotation_opts.objdump_path, "path",
> > "objdump binary to use for disassembly and annotations"),
> > OPT_STRING('M', "disassembler-style", &top.annotation_opts.disassembler_style, "disassembler style",
> > @@ -1651,6 +1652,8 @@ int cmd_top(int argc, const char **argv)
> > signal(SIGWINCH, winch_sig);
> > }
> >
> > + top.record_opts.bpf_event = !top.no_bpf_event;
> > +
> > status = __cmd_top(&top);
> >
> > out_delete_evlist:
> > diff --git a/tools/perf/util/top.h b/tools/perf/util/top.h
> > index 19f95eaf75c8..862a37bd27ea 100644
> > --- a/tools/perf/util/top.h
> > +++ b/tools/perf/util/top.h
> > @@ -32,6 +32,7 @@ struct perf_top {
> > bool use_tui, use_stdio;
> > bool vmlinux_warned;
> > bool dump_symtab;
> > + bool no_bpf_event;
> > struct hist_entry *sym_filter_entry;
> > struct perf_evsel *sym_evsel;
> > struct perf_session *session;
> > --
> > 2.17.1
> >
>
> Hi Arnaldo,
>
> Currently, we have bpf-event default OFF for perf-record, with option to
> turn it ON; while bpf-event is default ON for perf-top, with option to
> turn if OFF. I think this is a little confusing.
>
> How about we set them both to default ON, and add option to turn it OFF?

Agreed.

> I think we still have time to make the change.
>
> Thanks,
> Song
>
>

--

- Arnaldo